低氧习服对大鼠离体心脏缺血再灌注损伤的影响

Effects of hypoxic acclimatization on ischemia/reperfusion injury in isolated working hearts of rats

摘要:

目的研究急性低氧和间断低氧习服对大鼠离体心脏缺血/再灌注损伤的影响.方法经间断低氧习服(模拟海拔3000m,5000m低氧2周,每天4 h,最后8000m低氧4 h)和急性低氧(模拟海拔8000m低氧4 h)的大鼠,麻醉后开胸,迅速取出心脏,观察其离体心脏缺血/再灌注损伤情况.结果离体心脏缺血/再灌时的心率在第3min时最低,以后逐渐恢复,低氧习服组和急性低氧组的心率可恢复至缺血前水平,显著高于常氧对照组.反映心脏收缩功能的指标左心室收缩压(LVSP)和 dp/dtmax及反映心脏舒张功能的指标-dp/dtmax在复灌的第3～5 min时降至最低,心脏功能损伤较重,以后逐渐恢复.其中低氧习服组大鼠离体心脏的LVSP、 dp/dtmax和-dp/dtmax显著高于常氧对照组和急性低氧组.冠脉流出液中的肌酸磷酸激酶(CPK)亦在缺血/再灌后显著升高,且有不断升高的趋势,低氧习服组的CPK含量显著低于常氧对照组和急性低氧组.结论低氧习服可减轻大鼠离体心脏的缺血/再灌损伤.

Abstract:

Objective To study the effects of acute hypoxia and intermittent hypoxic acclimatization(HA) on ischemia/reperfusion(I/R) injury in isolated working hearts of rats. Methods The contractive and diastolic functions of isolated working hearts during ische